Author: Jovi Nazareno, Grad Student at Harvard University, Extension School
Have you ever read a catchy headline about the brain, brain health, how we use or should use our brain, or how much of the brain we use? Perhaps, like me, you have at some point been baited or even charmed into reading more. I find the brain and mind to be fascinating and would totally understand why you might feel the same way too.
My interest in learning about the brain and mind—and yes, I’m naming them separate although it could be debated whether they are one and the same—has motivated me throughout my graduate studies. While working toward a Master’s in Liberal Arts in Psychology, I have taken a handful of courses that include lessons on neuroscience, neuroanatomy, neurobiology, psychology, as well as education. A major takeaway so far has been the need to carefully and critically assess everything that I read, especially studies connecting some “neuro” aspect to behavioral (and even educational) findings. This is not to say that all findings cannot be trusted, but instead to be aware of the limitations and assumptions that are inherent to every study.
A brief overview of the basics
Findings about the brain as it relates to behavior (sometimes referred to as brain-behavior relationships or neural correlates) can generally be categorized under two main methods: lesion-based or activation-based. Lesion-based studies consider what happens when a particular part of the brain is disrupted or not in use (e.g., damage due to a stroke, tumor, trauma). This method attempts to correlate a behavioral observation (dysfunction) with a brain injury (e.g., lesion). On the other hand, activation-based studies consider what happens when the brain regions are working or are in use (e.g., while performing a task like speaking while in the MRI machine). This method attempts to correlate a behavioral observation with patterns of blood flow, which is assumed to represent increased neural activity in an area. 1
Beware of the fireworks
I’ll focus this blog post on considerations about activation-based methods, particularly from fMRI studies that many of us encounter. I’m focusing on fMRI because of interesting articles I came across after a lecture about the limitations of MRI/fMRI. During the lecture, 2 we were warned about what seems to be a popular catch-phrase about the brain—that it “lights up”!
After that class, out of curiosity, I googled, “brain lights up,” and found this headline: “Neuroimaging Illuminates How Gratitude Lights Up the Brain.” 3 Well, that sounds cool, right? Plus, gratitude must be a good thing if it is lighting up the brain, right? The title is certainly catchy, and something is interesting about the visual of my brain lighting up like fireworks when I practice/express gratitude. Yet, this title is the perfect example of the imprecise sharing of information.
Don’t be fooled by such headlines. The 5 Ws (and one H) are helpful tools. Consider, for example:
- Who did the study include?
- What exactly is the behavior of interest? What is being compared?
- Where did the study take place? Where in the brain is being investigated?
- When was the study published?
- Why is the study and/or findings so important?
- How did the investigators go about collecting and analyzing the data?
These types of questions are important because they help to distinguish the alluring but inaccurate findings from those that are methodologically sound. It also helps to know certain basics, like why “lighting up” is nothing more than click-bait. The phrase “lights up” feeds misunderstanding of what the imaging technology does and does not actually tell us, especially for people unfamiliar with the limitations of the technology. Spoiler alert: Nothing is “lighting up”. In fact, the phrase “lights up” is included in a list of terms to avoid. 4
To make matters worse, the online article about gratitude 3 shows an image of the brain. Such an image has the potential to encourage you as readers to believe what is being shared without questioning or going back to the primary source. For example, it has been found that including brain images changes the judgment about the reasoning provided in a study. 5 In the online article about gratitude, 3 the brain image shown is not even from the study being summarized! It is just there to grab your attention. Further, neuroscience evidence could be given relatively higher value even if the explanation is bad or the evidence is irrelevant. 6
A bite-size of technical information
fMRI is ultimately used to measure changes in oxygenated/deoxygenated blood flow, more commonly known as a BOLD signal or BOLD contrast. In other words, despite the wonderful technology, we are still left to make inferences that what is observed actually represents neuronal activity in the brain—which is debatable.
Additionally, imaging results from an fMRI scan must be carefully interpreted, as there is much complexity inherent in obtaining neuroimages, which involves comparative methods, statistical analyses, and data reconstruction.7 What we as readers see as images included in articles did not just show up during a scanning session—it is a result of computation and analysis.
Lastly, many studies involving humans are correlational in nature, not causal, meaning that we as investigators and as readers make inferences that blood flow indicates some important or meaningful change to a function (e.g., gratitude).
As you find yourself interested in learning about the brain, mind, and/or education, beware of the neuromyths, 8 false information, and click-bait. Ask questions of what you read, and share any questions you might have.
You may also find the following resources helpful and fun: